In 2003 Agüero became the youngest player to
debut in the Argentine First Division at 15 years
and 35 days, breaking the record previously set by
Diego Maradona in 1976.

His nickname, "Kun", was born when some
classmates noted that his hairdo looked like that
of Japanese anime character "Kum Kum."

Agüero has a tattoo on the inside of his right
arm, inscribed in Tengwar (a form of writing invented
by J.R.R. Tolkien and used by the Elves in his works).
It translates roughly to "Kun Aguero" in
the Latin alphabet.